I was using a chip AXI-060 (PSoC 5 architecture I think) before and was getting readings from some analog sensors (pressure transducers). Those readings were pretty accurate. I am now working with a 5 LP-032 chip, and I just notice that, even if I'm using the same code as on the AXI-060, those readings are completely different. I get a reading in mV that is about 3 times less than what I was getting with the old chip.

This is pretty scary. Any idea of what would cause that? Is the ADC different in PSoC 5 and PSoC 5LP?

I'm uploading the 2 projects. I just used my old project, the one I was using with a PSoC5 chip (on PSoC Creator 2.2), copied it to create the same project with a PSoC 5LP chip (on PSoC Creator 3.0). Some components were updated automatically, like the AMux, ADC and I added "-u _printf_float" in the Linker so that I can display the float values. I tried them both, and there are still a *3 difference between what I get with the 2 chips/boards.

I am using some boards that were designed by a startup company. The only thing they updated is the chip, at least I think.

Would it be possible that some settings in the updated components changed something?

Hi Dana, to answer you quickly for now, I'm getting 11mV on the PSoC 5LP project while I'm getting 32mV on the PSoC5 one. My output should be in the -35 to 35mV range. After comparing the 2 projects/board, I get a difference of about */2.8 to be exact.

I too guess the continous mode is the culprit here. The datasheets explicitely states its not suited when switching between signals. Use the multi-sample-mode, and stop/start the conversion between readings.

You also might want to add a bypassing cap for your Vref. This will reduce the noise, since your input voltages are rather small.

Even though the wait is about 1000 samples, I would not second-guess the datashett on that issue. Or do you know the DelSig-ADC so intimately that you know how many samples it takes to flush out old values from the decimator (the DS states that the continuous mode is the only one not flushing the decimator after each sample)?